A plasma treating apparatus adapted to provide a predetermined plasma treatment to an object W to be treated comprises a processing chamber 12 configured to be capable of being vacuumed, an object holding means 20 adapted to hold the object to be treated, a high frequency power source 58 adapted to generate high frequency voltage, a plasma gas supplying means 38 adapted to supply a plasma generating gas to be treated to generate plasma to the processing chamber, a pair of plasma electrodes 56, 56B connected to the output side of the high frequency power source via wirings 60 to generate plasma in the processing chamber, the pair of plasma electrodes being brought into an excited electrode state. In addition, a high frequency matching means 72 is provided in the middle of the wirings. In this case, each of the plasma electrodes 56A, 56B is not grounded. Thus, the plasma density can be increased, and the efficiency of generating plasma can be enhanced.